# US 2019/0377291 A1 · Fixing member and heat fixing device > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2019/0377291 A1 - Document ID: US20190377291A1 - Status: Published application - Kind: A1 - Application number: 16/425,104 - Filed: 2019-05-29 - Published: 2019-12-12 - Earliest claimed: 2018-06-07 - Assignees: Canon Kabushiki Kaisha - Applicants: Canon Kabushiki Kaisha - Inventors: Matsutaka Maeda; Yuji Kitano; Mamo Matsumoto; Katsuhisa Matsunaka; Yasuharu Notoya; Yo Imaizumi; Takuji Oishi; Yasuhiro Miyahara - Web page: https://patentgrep.com/patent/US20190377291A1 ## CPC - G03G 15/2057: {relating to the chemical composition of the heat element and layers thereof} - G03G 15/2064: {combined with pressure} - G03G 15/206: {Structural details or chemical composition of the pressure elements and layers thereof} - G03G 2215/2038: the belt further entrained around one or more rotating belt support members - G03G 2215/2048: Surface layer material - G03G 2215/2054: Inorganic filler, e.g. silica powder - G03G: ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY ## Abstract Provided is a fixing member includes: a substrate; and an elastic layer on the substrate, wherein the elastic layer contains a rubber and fillers dispersed in the rubber, and wherein an average value of area ratios of large-particle diameter fillers is 20% or more and 40% or less, and the large-particle diameter fillers have an average array degree fL of 0.00 or more and 0.15 or less, an average value of an area ratios of small-particle diameter fillers is 10% or more and 20% or less, the small-particle diameter fillers have an average array degree fS of 0.20 or more and 0.50 or less, and the small-particle diameter fillers have an average array angle ΦS of 60° or more and 120° or less. ## Claims ### Claim 1 A fixing member of an electrophotographic image forming apparatus comprising: a substrate; and an elastic layer on the substrate, the elastic layer containing a rubber and fillers dispersed in the rubber, wherein, assuming that five of binarized images each of which has a size of 150 μm×100 μm on any positions of a first section in thickness-peripheral directions of the elastic layer, and five of binarized images each of which has a size of 150 μm×100 μm on any positions of a second section in thickness-axial directions of the elastic layer are obtained, in each of the binarized images, the fillers are represented as white, and the rubber is represented as black, among the fillers in the binarized images, fillers having a circle-equivalent diameter of 5 μm or more are defined as large-particle diameter fillers, and fillers having a circle-equivalent diameter of less than 5 μm is defined as small-particle diameter fillers, and assuming that area ratios (%) of which a total areas of the large-particle diameter fillers with respect to the respective binarized images' areas are calculated, and area ratios (%) of which a total areas of the small-particle diameter fillers with respect to the respective binarized images' areas are calculated, an average value of the area ratios of the large-particle diameter fillers is 20% or more and 40% or less, and the large-particle diameter fillers have an average array degree fL of 0.00 or more and 0.15 or less, an average value of the area ratios of the small-particle diameter fillers is 10% or more and 20% or less, the small-particle diameter fillers have an average array degree fS of 0.20 or more and 0.50 or less, and the small-particle diameter fillers have an average array angle ΦS of 60° or more and 120° or less. ### Claim 2 (depends on 1) The fixing member according to claim 1, wherein a sum of the average value of the area ratios of the large-particle diameter fillers, and the average value of the area ratios of the small-particle diameter fillers, is 30% or more and 60% or less. ### Claim 3 (depends on 1) The fixing member according to claim 1, wherein the elastic layer has a tensile modulus of 0.20 MPa or more and 1.20 MPa or less. ### Claim 4 (depends on 1) The fixing member according to claim 1, wherein the elastic layer has a thermal conductivity in a thickness direction of 1.30 W/(m·K) or more. ### Claim 5 (depends on 1) The fixing member according to claim 1, wherein the substrate contains at least one kind selected from the group consisting of nickel, copper, iron, and aluminum. ### Claim 6 (depends on 1) The fixing member according to claim 1, wherein the fixing member comprises a fixing belt having an endless belt shape. ### Claim 7 (depends on 1) The fixing member according to claim 1, further comprising a surface layer on the elastic layer. ### Claim 8 A heat fixing device comprising: a heating member; and a pressurizing member arranged to face the heating member, wherein the heating member includes a substrate and an elastic layer on the substrate, the elastic layer containing a rubber and fillers dispersed in the rubber, assuming that five of binarized images each of which has a size of 150 μm×100 μm on any positions of a first section in thickness-peripheral directions of the elastic layer, and five of binarized images each of which has a size of 150 μm×100 μm on any positions of a second section in thickness-axial directions of the elastic layer are obtained, in each of the binarized images, the fillers are represented as white, and the rubber is represented as black, among the fillers in the binarized images, fillers having a circle-equivalent diameter of 5 μm or more are defined as large-particle diameter fillers, and fillers having a circle-equivalent diameter of less than 5 μm is defined as small-particle diameter fillers, and assuming that area ratios (%) of which a total areas of the large-particle diameter fillers with respect to the respective binarized images' areas are calculated, and area ratios (%) of which a total areas of the small-particle diameter fillers with respect to the respective binarized images' areas are calculated, an average value of the area ratios of the large-particle diameter fillers is 20% or more and 40% or less, and the large-particle diameter fillers have an average array degree fL of 0.00 or more and 0.15 or less, an average value of the area ratios of the small-particle diameter fillers is 10% or more and 20% or less, the small-particle diameter fillers have an average array degree fS of 0.20 or more and 0.50 or less, and the small-particle diameter fillers have an average array angle ΦS of 60° or more and 120° or less. ### Claim 9 (depends on 8) The heat fixing device according to claim 8, further comprising a heating unit configured to heat the substrate. ### Claim 10 (depends on 9) The heat fixing device according to claim 9, wherein the heating unit comprises an induction heating unit. ### Claim 11 (depends on 9) The heat fixing device according to claim 9, wherein the heating unit comprises a heater configured to heat the substrate. ### Claim 12 (depends on 11) The heat fixing device according to claim 11, wherein the heating member has an endless belt shape, and the heater is arranged so as to be in contact with an inner peripheral surface of the heating member.